Andy Murray has fallen to eighth in the world rankings - his lowest position since August 2008.

The Wimbledon champion's failure to defend his Sony Open title in Miami - he was beaten in the quarter-finals by eventual champion Novak Djokovic - saw him lose plenty of ranking points when the new list was published on Monday.

He consequently slips below both Tomas Berdych and Juan Martin Del Potro heading into the claycourt season. Given it is hardly his favourite period in the tennis calendar, Murray now runs the risk of falling out of the top eight before the French Open and Wimbledon in which case he could end up facing one of the top two seeds - likely to be Rafael Nadal or Djokovic - in the last 16.

Djokovic remains second to Nadal in the latest rankings, although his win in Miami, which came hot on the heels of success in Indian Wells, has seen him cut the gap to the Spaniard to fewer than 2,000 points.

Roger Federer returns to the top four for the first time since Wimbledon last year, replacing David Ferrer, who falls to sixth.

Australian Open champion Stanislas Wawrinka remains third with Berdych now fifth and Del Potro seventh.

Then comes Murray in eighth. The last time he was ranked that low he was just 21 and had yet to play in a Grand Slam final.